The child’s mother and three siblings escaped the blaze in Ingoldmells, Lincolnshire Police say.
A two-year-old girl has died in a fire at a seaside caravan park.
The blaze broke out in a static unit at Sealands caravan park in Ingoldmells, near Skegness, on Monday night.
Lincolnshire Police said the girl’s mother and three siblings managed to escape the blaze and have since been released from hospital.
Det Insp Jo Fortune said investigations were at an early stage and the cause of the fire was not yet clear.
She said teams would be working to piece together the circumstances of the “particularly harrowing” case over the coming days.
Lincolnshire Fire and Rescue Service said the fire was “well established” when crews arrived.
About 50 people from nearby caravans were evacuated to emergency accommodation set up by site owner Laver Leisure.
The force has appealed for any witnesses or people with footage of the fire to contact them.
Sealands is a coastal holiday home site with 263 static home plots, many of which can be rented.
It is popular with holidaymakers and is close to Fantasy Island theme park and a Butlin’s holiday camp.
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